Artificial tooth



Jan. 22, 1929. 1,699,854

' s. MYERSON ARTIFIC IAL TEETH Original Filed Jan. 15. 1925 Invfl'br Simon myerson Patented Jan. 22, 1929.

UNITED STATES 1,699,854 PATENT OFFICE.

SIMON MYERSON, F CAMBRIDGE, MASSACHUSETTS.

ARTIFICIAL TOOTH.

Application filed January 15, 1925, Serial No. 2,542. Renewed June 2, 1928.

This invention relates to an artificial denture including an artificial tooth and a molded vulcanite or other plate, to which the tooth is attached.

The chief object of the invention is to provide a tooth, the lingual faceof which is fully exposed, instead of being partially overlapped by a portion of the plate as heretofore in this class of dental work, so that the lingual face closely resembles that of a natural tooth, in that it has a natural feeling in the mouth, and permits better articulation in speaking than the lingual face of a tooth in an artificial denture, overlapped to a considerable extent by the plate, as required by the tooth formation heretofore provided.

This object is attained by providing a new and improved form and construction of the basal portion'of the tooth, whereby a strong attachment of the tooth to the plate may be effected, without causing the plate to over lap the lingual face.

Of the accompanying drawing forming a part of this specification,-

Figure 1 is an edge view, on an enlarged scale, of an artificial tooth embodying the invention.

Figure 2 is a rear view, looking toward the lingual face.

Figure 3 is a perspective view.

Figure 4 shows the tooth in longitudinal section and a portion of a vulcanite plate to which the tooth is fixed.

Figure 5 is a view similar to Figure 1, showing a different form of the ridge lap.

The same reference characters indicate the same parts in all of the figures.

12 designates the lingual face, and 13 the labial face of a tooth to which my invention relates, these being of any suitable form.

The ridge lap of my improved tooth includes an outer face portion 14, which bears on the usual vulcanite plate 16, as shown by Figure 4, and an inner face portion 15, which is embedded in the plate. The inner face portion 15 is approximately at right angles with the longitudinal median line of the tooth, so that it is adapted to cooperate with the plate in supporting outward pressure, caused by a bite when the tooth is in use, so that the force of mastication is effectively resisted. The outer face portion 14 is inclined upwardly and outwardly from the inner face portion 15, at an angle to the labial face 13,

so that the tooth may be freely withdrawn from a mold in which it is formed, and is free from liability to break crosswise of the ridge lap.

I and enabled by this arrangement to so limit the entrance of the tooth into the plate 16, that the entire area of the lingual face 12 is exposed to contact with the tongue, and is not overlapped to any appreciable extent by the plate. a v 7 To compensate for this absence of overlap of the lingual face by the plate, and the increased leverage exerted by masticating force, and further, to provide a connection resisting any strains liable to displace the tooth, I provide the inner face portion 15 with an undercut margin 18, adapted to be interlocked with the portion of the plate in which the inner face is embedded and cooperate therewith in supporting pressure tending to tip the tooth forward and outward. Said margin has a midlength portion of maximum width adjacent to the lingual face, decreasing in width toward the labial face and merging into the outer face portion of the ridge lap, at a distance from the labial face, so that the outer face portion 14l1as the full width of the tooth from side to side, and a. maximum resistance to. breakage crosswise of the ridge lap.

To further increase the strength of the connection of the tooth with the plate, I provide a metal anchoring pin 19, including an inner portion embedded in the tooth, and preferably provided with a head 20, and an outer portion projecting from the inner face por tion 15, and provided with a head 21, the said outer portion being adapted to be embedded in the plate 16, as shown by Figure 4.

The-useful features above stated may be embodied in a tooth of simpler form, smaller bulk, and greater strength than any hereto fore produced and easier of manipulation, so far as I am aware, the whole retentive structure being within the basal periphery of the tooth.

The provision of the undercut margin 18 results in the formation of a marginal face 15 at the base of the undercut margin, offset from the inner face portion 15 and supplementing the latter. Said marginal face is offset by the undercut margin 18, from the inner face portion 15, and merges into the outer face portion 14.

The face portions 14 and 15 impart a recessed form to the ridge lap. When these portions are curved, as shown by- Figures 1 to 4, the recess is of minimum depth.

In some cases it is desirable to provide a deeper recess by making the face portions 14 and 15 substantially flat, so that they meet to form an obtuse angle, as shown by Figure 5. This deeper recess provides more room between the ridge lap and the ridge in the mouth on which the plate 16 bears, which is often an advantage.

I claim:

1. An artificial tooth having a lingual face, a labial face and a ridge lap including an illner face portion approximately at right angles to the longitudinal median line of the into the outer face portion of the ridge lap at a distance from,the labial face, sothat said outer face portion has the full width of the tooth from side to side, and a maximum resistance to breakage crosswise of the ridge lap, the ridge lapbeing provided with a marginal face offset by the undercut margin from its inner face portion, and merging into its outer portion.

2. An artificial tooth having a lmgual face,

a labial face, and a ridge lap including an inner face portion approximately at right angles to the longitudinal median line of the tooth, and adapted to cooperate with a vu1- canite plate in supporting pressure caused by a bite, and an outer face portion inclined upwardly and outwardly from the inner face portion, at an angle to the labial face, so that the tooth is free from liability to breakage crosswise of the ridge lap the inner faceportion being provided with an undercut margin, adapted to be interlocked with a vulcanite plate, and cooperate therewith in supporting pressure tending to tip the tooth forward and outward, said margin havin a midlength portion of maximum width a jacent to the lingual face, decreasing in width toward the labial face, and merging into the outer face portion of the ridge lap at a distance from the labial face, so that said outer face portion has the full width of thetooth from side to side, and a maximum resistance to breakage crosswise of the ridge lap, the

ridge lap being provided with a marginal face offset by theundercut margin from its inner face portion, and merging into its outer portion, the tooth being provided with a headed anchoring pin projecting from the inner face portion of the ridge lap, and

adapted to cooperate with the plate and with the undercut margin in preventing separation of the ridge lap from the plate.

In testimony whereof I have fli y signature.

SIMON YERsoN. 

